/*
 * Copyright 2011-2012 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.sabayframework.mem.impl.disk;

import java.io.IOException;

import org.sabayframework.mem.Memorizable;
import org.sabayframework.mem.impl.TransactionImpl;

public class PessimisticTxActivity extends NoLockTxActivity {

	public PessimisticTxActivity(TransactionImpl transaction, DiskSpace tm) throws IOException {
		super(transaction, tm);
	}

	@Override
	protected Memorizable[] read(Class<? extends Memorizable> objectClass,	long[] ids) throws Exception {
		if(!tx.tryLock(ids)) return null;
		return super.read(objectClass, ids);
	}

	@Override
	protected boolean write(Memorizable[] rs) throws Exception {
		long addresses[] = new long[rs.length];
		for(int i=0;i<rs.length;++i){
			addresses[i] = rs[i].getId();
		}
		if(!tx.tryLock(addresses)) return false;
		return super.write(rs);
	}

	@Override
	protected boolean delete(long[] ids) throws Exception {
		if(!tx.tryLock(ids)) return false;
		return super.delete(ids);
	}

}
